1. Field of the Invention
This invention relates to the fabrication of molded brassiere pads.
2. Prior Art
Brassiere pads molded from fiberfill material of varying thicknesses have been made for many years. Prior art processes have suffered from thinning at the apex while forming the pad to the required contour and consequently have resulted in poor washability. In order to avoid thin spots or tears at the apex of the pad, it has been common to use a cut and sewn or preformed blank of material having roughly the finish contours desired. Such preforms have been made, for example, by cutting a pie-shaped segment out of a flat blank and sewing or gluing the cut edges to form a conical shape. Another method of fabrication involves making a single cut part way across the pad and overlapping the material on each side of the cut, followed by gluing or sewing.
These methods avoid the problem of thinness at the apex of the pad. However, the glued or sewn seam pad is always visible and felt through the outer fabric which is generally applied over the inside and outside thereof. The purpose of a bra pad is to enhance the apparent size of the breast without making the presence of a pad obvious. In order to accomplish this, the pad should be relatively heavy at the apex and thin gradually to the periphery. The invented method and apparatus thins out selected portions of the blank, leaving the apex heavy, and at the same time forms the blank into the proper conical shape for insertion into a heated mold for final forming, resulting in a totally seamless pad which can be lined totally to create a sandwich therewith.
The fiberfill material used in the invented pad preform is a nonwoven fibrous batting material which is comprised of relatively short polyester fibers randomly packed and bound together with an acrylic resinous binder. The fibers are loosely packed and are compressed in the pad molding operation so that the desired softness of the pad is obtained. In order for the material to retain the desired density and the form of the mold, the mold is heated, typically from 300.degree. to 450.degree. F so that the binder resin will cure with the fibers compressed in the mold. The resin, however, is 75 to 80% cured when the fiberfill sheet is received. In the drawing operation, prior to molding the bonding between the individual fibers is partially broken, resulting in weakening of the fiberfill pad, so that it has a reduced life, especially under continued washing causing, the contour shape to be lost. The invented method overcomes this problem by introducing additional acrylic resin, of the same type as used to bond the fibers in the original sheet, and which rebonds any bonds broken in the curing cycle. The additional bonding agent, when cured, also reinforces unbroken bonds in the sheet.
Another prior art approach involves the use of a flat sandwich of fiberfill material which is placed between two layers of liner material. This sandwich is then placed in a two-part mold where it is first shaped thereby in a bra shape mold. In this process the fibers of the fiberfill and the molding agent break down. Additionally, the apex flattens out, thus still leaving the basic problems unresolved.